将源字符串的前count个字符拷贝到目的字符串中
char *strncat(char *dest, const char *src, size_t count)
{assert((NULL != dest) && (NULL != dsrc));char *cp = dest;if (0 == count)//返回原来的{return dest;}while (*cp != '\0'){cp ++;}while (count-- > 0){if (!(*cp++ = *src++)) //'\0'{return dest;}}*cp = '\0';return dest;
}
)
)
)
